例句： Before I wind up, there are two more things to be said.

例句： The surgeon has performed the operation.

例句： The plane answered smoothly to the controls.

例句： The soldiers bedded down in a barn.

例句： The metal tool clanged when it hit the ground.

例句： The purchase price is less if you pay by cash.

例句： Our teacher is a very responsible person.

例句： He leaves a widow and two children.

例句： Many people would like to take holidays abroad.

例句： The solar cell can convert the energy of sunlight into electric energy.